There are three paths you can take when creating paths (sorry, I couldn't resist):
Create a path directly from a selection you've already made.
Create a path from scratch by using the Pen tools and drawing the path by hand.
Create a path using the Shape tools.
Depending on the image at hand, simply making a selection and converting it to a path can be the easiest and quickest way to create a path.
Let's look at an example. Figure 13.1 shows the test image, a tire gauge. We'll select the object, and make what's called a clipping path, clipping it out of the background. Without Photoshop, you would achieve the same effect with a photographic print and a pair of scissors.